The present invention relates to a machine and procedure for packing of nail plates.
Sheet metal plates having a plurality of teeth struck out from the plates so as to form nails have been marketed for many years for use in the construction industry for forming wooden joints. Exemplary of these types of nail plates are those shown in U.S. Pat. No. 3,390,902 to J. C. Jureit entitled WOOD JOINT AND CONNECTOR THEREFORE and U.S. patent application Ser. No. 71,551 to Moyer et al. filed Aug. 30, 1979 and entitled STRUCTURAL JOINT CONNECTOR, now U.S. Pat. No. 4,343,580, the subject matter of both of which are hereby incorporated by reference.
These various nail plates are formed by feeding a continuous web of sheet metal (typically 18 or 20 gauge) into a stamping machine. In the stamping machine, with the use of punch and die sets, the teeth are stamped out of the continuous web of sheet metal. In addition, the sheet metal is at least partially or totally scored for separating the sheet metal web into the various separate plates.
As the stamped out nail plates exit from the stamping machine, the plates are packed by any one of a variety of techniques, most of which are extremely labor intensive in carrying out such operations. The various common techniques for packing the nail plates exiting from the stamping machine include: tumble packing the plates in a box; hand packing the plates with the teeth of adjacent plates facing each other and intermeshed then placing them in a box; forming a stack of breakaway plates where the plates are only partially scored and stored in long sheets; rolling a continuous stream of the plates onto a spool so as to form a coil of the nail plates; and forming bar stock where the teeth are only scored so as to form large sections such as section 6 inches by 48 inches which are then further cut by the customer. Several of these operations include manually pairing and stacking the plates or sheets of plates, which stacks then can be packed in a box or banded together. Exemplary of the packing operation in which large scored sheets or uncut sheets are stacked is illustrated in U.S. Pat. No. 3,963,452 to J. C. Jureit et al. Exemplary of a packing operation in which coils of the nail plate stock are rolled up on a spool are illustrated in U.S. Pat. Nos. 3,895,708 to J. C. Jureit et al. and 4,129,933 to J. C. Jureit et al.
The general type of packing operation of primary concern in connection with the present invention relates to that type of operation in which either the connector plates or sections of plates are arranged in stacks. These stacks then are packed in a box for shipment or the sections of plates are banded together and shipped.
In tumble packing the connector plates, as the plates exit from the stamping machine they have been totally scored so as to form the separate plates. The plates then are merely conveyed along a conveyor belt and dropped into a box located at the end of such belt, i.e. tumble packed in the box. While the tumble packing operation is relatively inexpensive since there is very little labor involved in the packing operation there is a large amount of space inefficiency since the box is not packed with as great a quantity of plates as possible with other packing techniques. Alternatively, the plates can be formed in a stack with the teeth of adjacent plates being intermeshed and then stacks of plates placed in the box; this technique is carried out in a hand packing operation which is highly labor intensive thereby tremendously increasing the cost of such packing operation. The hand packing of the plates in the box, however, provides for a much greater concentration of the plates in the box so as to increase space efficiency. The other techniques for forming stacks of plates, either breakaway plates or bar stock where the plates are later cut at the customer location, are efficient from the viewpoint of shipping of the plates but require a tremendous amount of labor since the stacks are formed by operators picking up each individual plate or strip of plates and forming the stacks.